Trying ribs for the second time. First time I cooked with indirect heat (250 degrees) uncovered for 1.5 hours and then covered for 2.5 hours and uncovered for the final 10 minutes (at around 350) directly on the grate without the place setter. Is there a better ratio of uncovered to covered? Or does it really matter? The first time the ribs were good, but I want them to be great! Thanks for the input!!!! Any other advice would be greatly appreciated.